1. Field of the Invention
The present invention relates to a release composition for hydraulic bonding materials such as, e.g., concrete, and to methods for using such release composition to facilitate unmolding operations and for casting molded pre-formed articles.
2. Description of Prior Art
It is known in the art of molding concrete pieces to coat those mold surfaces which come into contact with the material being molded with a product which facilitates the unmolding and which attains a satisfactory surface condition for the pieces. The release compositions presently used are constituted essentially, according to various formulas, of a mixture of organic solvents and petroleum products to which are added active release ingredients.
Emulsions which include a percentage of petroleum products and which are stable to a greater or lesser degree over time have also been proposed. The use of petroleum products tends to inflate the cost of these release compositions. Moreover, the presence of these solvent/petroleum oil mixtures necessitates a drying period for the unmolded surfaces before any other treatment, such as painting, can be effected, since paint would not adhere to a wet treated surface.